Sussex detectives are hoping two new TV appeals this week and massive rewards will help put the men responsible for horrific crimes behind bars.

Senior investigators are also set to reveal that the reward for the conviction of the killer of schoolgirl Sarah Payne now stands at more than £150,000 thanks to offers from the public and media.

The reward includes £10,000 offered by the Evening Argus just days after the discovery of Sarah's body shocked the nation. A major reconstruction showing Sarah's last movements will be screened during Crimewatch UK on Wednesday night. The eight year-old was snatched on July 1 as she walked back to her grandparents home in Kingston Gorse near Littlehampton after playing in a field with her two brothers and sister. Her naked body was found partiallty buried in a field next to the A29 at Pulborough 16 days later.

Detectives are hoping that the BBC's Crimewatch programme will bring in vital new information about the white transit style van which police believe was used to abduct Sarah.

The investigation, codenamed Operation Maple, has so far cost £1.4 million and 50 detectives are still assigned to the case.

Meanwhile members of the Operation Bobcat team are also hoping that the programme will help catch a serial sex attacker who has raped one woman and indecently assaulted 14 others during a four year reign of terror in the Chichester and Bognor areas.

More than 300 men matching a profile and description of the attacker have taken voluntary DNA tests after police revealed they have forensic evidence from two attacks which are identical.

But none have so far proved positive and new information will be revealed during the programme about a man dubbed the Thursday Night rapist because of the day of the week when most of the attacks have taken place.

Rewards totalling £50,000 have been put up as part of the appeal for help to find the man who has stalked many of his victims before attacking them in their own homes. Other victims, many of them students, have been attacked as they walked alone in secluded areas such as subways and footpaths. Safety warnings have been issued to hundreds of students attending language schools and undergraduates from University College Chichester which also has a campus at Bognor.